It seems an experimental feature being tested by RIPE in their BGP announcements yesterday at around 9 am UTC caused several Internet Service Providers -- mostly in Europe -- to lose connection with their peers, temporarily cutting off or disrupting Internet connectivity in several countries.

The problem may have been caused by a faulty BGP implementation in some core routers, which corrupted the new attribute before propagating it to their peers and/or reacted to what they perceived as an invalid BGP attribute by resetting the peering session.